Welcome to the zany world of Melita Pargeter, a slightly surreal orbit populated by Runyonesque characters like Concrete Jacket, Fossilface O'Donahue and Keyhole Crabbe--all mildly disreputable, all owing debts of gratitude to the late Mr. Pargeter. When Melita decides to construct a country home an hour from London, she hires builder Concrete Jacket, who, like all the shady but nonviolent felons in this comic mystery, shows deference and deep respect to the widow. But when the body of a small-time hood is found in Melita's basement and Concrete is arrested for murder, Melita is astonished that the shrewd and able construction expert (famous for his tunneling) refuses any defense. Is he being framed? Is it blackmail? She immediately plunges into her own investigation, utilizing a colorful network of unscrupulous characters who discretely escape jail, break and enter and carefully eavesdrop in order to find out who is behind the murder. There are global implications, and Melita, comfortably affluent and never without a devious idea, puts together a scheme of her own. Now she is at considerable risk. This fourth in the Pargeter series (after Mrs. Pargeter's Pound of Flesh) is sparkling, lively, full of surprises and, like a good plate of fish and chips, topped with a touch of vinegar. (Jan.)